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Show GALAPAGOS ARCHIPELAGO. Oct. 1835. seems to be a wanderer from the continent. Of sh:lls, there are a considerable number of land kinds, all of wh1~h, I believe are confined to this archipelago. Even of marme species, a large proportion were not kn?wn, before the collection made by Mr. Cuming on these Islands was brought to England. I ill not here attempt to <!Orne to any definite conclu- w . d sions, as the species have not been. accurately examme ; but we may infer, that, with the exception of a few wand~rers, the organic beings found on this archipelago are pecuhar to it; and yet that their general form strong~y partakes of an American character. It would be impossible for any one accustomed to the birds of Chile and La Plata to be placed on these islands, and not to feel convinced that he was, as far as the organic world was concerned, on American ground. This similarity in type, between distant islands and continents, while the species are distinct, has scarcely been sufficiently noticed. The circumstance would be explained, according to the views of some authors, by saying that the creative power had acted according to the same law over a wide area. It has been mentioned, that the inhabitants can distinguish the tortoises, according to the islands whence they are brought. I was also informed that many of the islands possess trees and plants which do not occur on the others. For instance the berry-bearing tree, called Guyavita, which is common on James Island, certainly is not found on Charles Island, though appearing equally well fitted for it. U nfortunately, I was not aware of these facts till my collection was nearly completed: it never occurred to me, that the productions of islands only a .few miles apart, and placed under the same physical conditions, would be dissimilar. I therefore did not attempt to make a series of specimens from the separate islands. It is the fate of every voyager, when he has just discovered what object in any place is more particularly worthy of his attention, to be hurried from it. In the case of the mocking-bird, I ascertained (and have Oct. 1835. 'rAMENESS OF BIRDS. brought home the specimens) that one species ( 01'pheus trifasciatus, Gould) is exclusively found in Charles Island ; a second ( 0. parvulus) on Albemarle Island; and a third (0. melanotus) common to James and Chatham Islands. The two last species are closely a1lied, but the first would be considered by every naturalist as quite distinct. I examined many specimens in the different islands, and in each the respective kind was alone present. These birds agree in general plumage, structure, and habits ; so that the different species replace each other in the economy of the different islands. These species are not characterized by the markings on the plumage alone, but likewise by the size and form of the bill, and other differences. I have stated, that in the thirteen species of ground-finches, a nearly perfect gradation may be traced, from a beak extraordinarily thick, to one so fine, that it may be compared to that of a warbler. I very much suspect, that certain members of the series are confined to different islands ; therefore, if the collection had been made on any one island, it would not have presented so perfect a gradation. It is clear, that if several islands have each their peculiar species of the same genera, when these are placed together, they will have a wide range of character. But there is not space in this work, to enter on this curious subject. Before concluding my account of the zoology of these islands, I must describe more in detail the tameness of the birds. This disposition is common to all the terrestrial species; namely, to the mocking-birds, the finches, sylvicolre, tyrant-flycatchers, doves, and hawks. There is not one which will not approach sufficiently near to be killed with a switch, and sometimes, as I have myself tried, with a cap or hat. A gun is here almost superfluous; for with the muzzle of one I pushed a hawk off the branch of a tree. One day a mocking-bird alighted on the edge of a pitcher (made of the shell of a tortoise), which I held in my hand whilst lying down. It began very quietly to sip the water, and allowed me to lift it with the vessel from the ground. |